Explosive.



v I PATEN QFFI E.

- ExrLosI'vE.

Letters Patent; 1 Patented Sept.1 0,1912 i 1,038,18". "Specification or ".no mess i fipplication filed September 5, 911. Serial No. 647,474.

To zz-wmem conccm:

Be it wn that I, Jamie F. OBRIEN, a. citizen, of the States, residing-at .Gbicag'o, in the county of Cook, State of '5 lllinoi's, -haveinvented new and useful Imi'ovemeiits in Explosives,of which the fol- 5 owing-is za'speciiicationg gzrhi' invention relatesjto an explosive may be re'g'a'rded as aderivative of an explosive for 'whichi I have filed application for-United. States Letters Patent on Se temb'r 5th, 19l1, bearing Serial No. 64 ,473 and the present invent on'consis'ts in certain 1 h ng swfi 'add en' to hei m l theregreatly. cheaper' in manufacture and onl' sli htl 7 quah erior in explosive g I r QY9l I IM 9 L we flescribedfas-agbasls for. that explosive ersgem rstaei alkali metal o hy lf ifi approximate proortion -'bne: mixture forms. i lcsive'ef this application; nd difference between this and the otherl explosiveis {the addition of -a certain amount of silico-aluminous' material, such as finely powdered brickdust, to form an inert body forthe explosive and .to reduce -,its-cost ofjmanufacture. But, while reducingthe cost'of .manuiacture, the insertion of "this comparatively inertsubstancadoes not. reducelthefexplosiveenergy of the powder in-thefs'ameflratio so-that, value for Value, T 3 thisipow'derbfthepresent application willv .do more-Wdrkthanthe-powder of the appli cation-above referred-to.

f the on a In its andni'cistpreferred' form my present explosive con'sists o fpotassiiun V chlorate abiiutsixty percent, sugar: about e'ghteen'per cent;, starch :ab'out two per cent. and -finly pulverized brick dust about twenty percent-1 The proportion of brickidilstmay be increased to as much as thirty-. five or fforty'r'per cjerit. o'fthe wholerweight, thereby decreasing: the -we'ightof the chlo rate and "'ofthe carboI-hydrate Butltheweight of the chlorateandthe carbc-hyd'rate m'ost .efiiciently-kept-at the ratio. of ap,- proximately three to one. =The amouiitof sugar; or of starchmay bevaried providing th'e'total of carbo-hydrate be kept at-approximately one-third the Weight of the chlorate. Thus, I may utilizeten per cent.

o starch and ten per cent. of sugar together blast them into small pieces.

' pulverized brick dust are mixed together and the-sugar is then mixed with this mix .ture. -Th e starch 'or'other carbohydrate is mixed with the sugarbefore being mixed with the other ingredients-or the ingredients may all be-mixed together at one time. After m xing, the mass ably granulated.

.. In order to control the ,speed of combusutilize a, small 1 amount" of fiierric ferro- .With-sixty per cent. of the chlorate. Other is dried and. suit:

Iv o t on of this explosive, as-in the-Qexplosive' 2*; of the application above. referred to, I may two per centf of the whole explosives 'ThlS cyanogen compound may be'inixedwithlthe sugar before the sugar is mixed-.withthe otheringredients-or 1t may" be placed in the;

mixture while they are being mixed together; The cyanogen compound has, the

efi'ect of increasing the speed of c'o'mbusti'on as more is added" to the explosive; two pounds of the cyanogen compound in two thousand pounds of the explosive renders the powder-extremely quick in combustion, resembling the explosion of dynamite or nitroglycerin. Without any of thecyano-.

gen compound, or with a very small amount,

the combustion is -comparatively slow and the powderis adapted particularly for work.

in soft materials where it is desired not to The explosive as abuVe described has the advantage of being extremely simple in composition and preparation and of ye'ry low manufacturing ;cost.. The addition of the- .brick dust.'f(calcined clay) greatly reduces the manufacturing cost "without proportionately reducing the explosive energy. Al-

though, the brick dust is a comparatively inert" substance, I have foundithat it {adds materially to the explosive-energy ofthe explosive. Th'at'is, the additionof a certain amount of calcinedclay to a certain mass of carbo-hydrate and chlorate will increase the explosive energy of the mass, but will somewhat decrease its 1explosive energy per unit mass. The amount of brick dust may be varied to suit condi .tions; for ordinary purposes about twenty 

